<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html lang="en">
<head>
<title>Life Lexicon (M)</title>
<meta name="author" content="Stephen A. Silver">
<meta name="description" content="Part of Stephen Silver's Life Lexicon.">
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<link href="lifelex.css" rel="stylesheet" type="text/css">
<link rel="begin" type="text/html" href="lex.htm" title="Life Lexicon">
<base target="_top">
</head>
<body bgcolor="#FFFFCE">

<center><A HREF="lex.htm">Introduction</A> | <A HREF="lex_bib.htm">Bibliography</A></center></center>
<hr>
<center>
<font size=-1><b>
<A HREF="lex_1.htm">1-9</A> |
<A HREF="lex_a.htm">A</A> |
<A HREF="lex_b.htm">B</A> |
<A HREF="lex_c.htm">C</A> |
<A HREF="lex_d.htm">D</A> |
<A HREF="lex_e.htm">E</A> |
<A HREF="lex_f.htm">F</A> |
<A HREF="lex_g.htm">G</A> |
<A HREF="lex_h.htm">H</A> |
<A HREF="lex_i.htm">I</A> |
<A HREF="lex_j.htm">J</A> |
<A HREF="lex_k.htm">K</A> |
<A HREF="lex_l.htm">L</A> |
<A HREF="lex_m.htm">M</A> |
<A HREF="lex_n.htm">N</A> |
<A HREF="lex_o.htm">O</A> |
<A HREF="lex_p.htm">P</A> |
<A HREF="lex_q.htm">Q</A> |
<A HREF="lex_r.htm">R</A> |
<A HREF="lex_s.htm">S</A> |
<A HREF="lex_t.htm">T</A> |
<A HREF="lex_u.htm">U</A> |
<A HREF="lex_v.htm">V</A> |
<A HREF="lex_w.htm">W</A> |
<A HREF="lex_x.htm">X</A> |
<A HREF="lex_y.htm">Y</A> |
<A href="lex_z.htm">Z</A></b></font>

</center>
<hr>
<p><a name=mango>:</a><b>mango</b> (p1)
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
.OO..
O..O.
.O..O
..OO.
</a></pre></td></tr></table></center>
<p><a name=mathematician>:</a><b>mathematician</b> (p5) Found by Dave Buckingham, 1972.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
....O....
...O.O...
...O.O...
..OO.OO..
O.......O
OOO...OOO
.........
OOOOOOOOO
O.......O
...OOOO..
...O..OO.
</a></pre></td></tr></table></center>
<p><a name=max>:</a><b>Max</b> A name for the smallest known <a href="lex_s.htm#spacefiller">spacefiller</a>. The name represents
the fact that the growth rate is the fastest possible. (This has not
quite been proved, however. There remains the possibility, albeit
not very likely, that a periodic <a href="lex_a.htm#agar">agar</a> could have an average
<a href="lex_d.htm#density">density</a> greater than 1/2, and a spacefiller stretching such an
agar at the same speed as the known spacefillers would have a faster
average growth rate.)
<p><a name=mazing>:</a><b>mazing</b> (p4) In terms of its minimum <a href="lex_p.htm#population">population</a> of 12 this ties with
<a href="#mold">mold</a> as the smallest p4 <a href="lex_o.htm#oscillator">oscillator</a>. Found by Dave Buckingham in
December 1973. For some constructions using mazings, see <a href="lex_p.htm#popover">popover</a>
and <a href="lex_s.htm#sixtynine">sixty-nine</a>.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
...OO..
.O.O...
O.....O
.O...OO
.......
...O.O.
....O..
</a></pre></td></tr></table></center>
<p><a name=mediumfish>:</a><b>medium fish</b> = <a href="#mwss">MWSS</a>
<p><a name=metacatacryst>:</a><b>metacatacryst</b> A 52-cell pattern exhibiting quadratic growth. Found
by Nick Gotts, December 2000. This is currently the smallest known
pattern (in terms of initial population) with superlinear growth.
See also <a href="lex_c.htm#catacryst">catacryst</a>.
<p><a name=metamorphosis>:</a><b>metamorphosis</b> An <a href="lex_o.htm#oscillator">oscillator</a> built by Robert Wainwright that uses
the following reaction (found by Bill Gosper) to turn <a href="lex_g.htm#glider">gliders</a> into
<a href="lex_l.htm#lwss">LWSS</a>, and converts these LWSS back into gliders by colliding them
head on. (There are in fact two ways to do the following reaction,
because the <a href="lex_s.htm#spark">spark</a> of the <a href="lex_t.htm#twinbeesshuttle">twin bees shuttle</a> is symmetric.)
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
...................O.........
....................O........
..................OOO........
.............................
.............................
.............................
.............................
.............................
............O...O.....O.OO...
OO.........O.....O....O.O.O..
OO.........O.........O....O..
...........OO...O.....O.O.O..
.............OOO......O.OO...
.............................
.............OOO.............
...........OO...O............
OO.........O...............OO
OO.........O.....O.........OO
............O...O............
</a></pre></td></tr></table></center>
<p><a name=metamorphosisii>:</a><b>metamorphosis II</b> An oscillator built by Robert Wainwright in
December 1994 based on the following p30 <a href="lex_g.htm#glider">glider</a>-to-<a href="lex_l.htm#lwss">LWSS</a>
<a href="lex_c.htm#converter">converter</a>. This converter was first found by Paul Rendell,
January 1986 or earlier, but wasn't widely known about until
Paul Callahan rediscovered it in December 1994.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
......................O.
.....................O..
.....................OOO
........................
........................
.........O.O............
.........O..O...........
OO..........OO..........
OO........O...OO........
.....OO.....OO..........
....O....O..O...........
.........O.O............
........................
........................
........................
........................
................O.......
...............OOO......
..............OOOOO.....
.............O.O.O.O....
.............OO...OO....
........................
........................
................O.......
...............O.O......
...............O.O......
................O.......
...............OO.......
...............OO.......
...............OO.......
</a></pre></td></tr></table></center>
<p><a name=methuselah>:</a><b>methuselah</b> Any small pattern that stabilizes only after a long
time. Term coined by Conway. Examples include <a href="lex_r.htm#rabbits">rabbits</a>, <a href="lex_a.htm#acorn">acorn</a>,
the <a href="lex_r.htm#rpentomino">R-pentomino</a>, <a href="lex_b.htm#blom">blom</a>, <a href="lex_i.htm#iwona">Iwona</a>, <a href="lex_j.htm#justyna">Justyna</a> and <a href="lex_l.htm#lidka">Lidka</a>. See also
<a href="lex_a.htm#ark">ark</a>.
<p><a name=mickeymouse>:</a><b>Mickey Mouse</b> (p1) A name proposed by Mark Niemiec for the following
<a href="lex_s.htm#stilllife">still life</a>:
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
.OO....OO.
O..O..O..O
O..OOOO..O
.OO....OO.
...OOOO...
...O..O...
....OO....
</a></pre></td></tr></table></center>
<p><a name=middleweightemulator>:</a><b>middleweight emulator</b> = <a href="#mwemulator">MW emulator</a>
<p><a name=middleweightspaceship>:</a><b>middleweight spaceship</b> = <a href="#mwss">MWSS</a>
<p><a name=middleweightvolcano>:</a><b>middleweight volcano</b> = <a href="#mwvolcano">MW volcano</a>
<p><a name=minipressurecooker>:</a><b>mini pressure cooker</b> (p3) Found by Robert Wainwright before
June 1972. Compare <a href="lex_p.htm#pressurecooker">pressure cooker</a>.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
.....O.....
....O.O....
....O.O....
...OO.OO...
O.O.....O.O
OO.O.O.O.OO
...O...O...
...O.O.O...
....O.O....
.....O.....
</a></pre></td></tr></table></center>
<p><a name=mipvalue>:</a><b>M.I.P. value</b> The maximum <a href="lex_p.htm#population">population</a> divided by the initial
population for an unstable pattern. For example, the
<a href="lex_r.htm#rpentomino">R-pentomino</a> has an M.I.<i>P</i>. value of 63.8, since its maximum
population is 319. The term is no longer in use.
<p><a name=mitoscillator>:</a><b>MIT oscillator</b> = <a href="lex_c.htm#cuphook">cuphook</a>
<p><a name=mmmbreeder>:</a><b>MMM breeder</b> See <a href="lex_b.htm#breeder">breeder</a>.
<p><a name=mmsbreeder>:</a><b>MMS breeder</b> See <a href="lex_b.htm#breeder">breeder</a>.
<p><a name=mod>:</a><b>mod</b> The smallest number of generations it takes for an <a href="lex_o.htm#oscillator">oscillator</a>
or <a href="lex_s.htm#spaceship">spaceship</a> to reappear in its original form, possibly subject to
some rotation or reflection. The mod may be equal to the <a href="lex_p.htm#period">period</a>,
but it may also be a quarter of the period (for oscillators that
rotate 90 degrees every quarter period) or half the period (for other
oscillators which rotate 180 degrees every half period, and also for
<a href="lex_f.htm#flipper">flippers</a>).
<p><a name=mold>:</a><b>mold</b> (p4) Found by Achim Flammenkamp in 1988, but not widely known
until Dean Hickerson rediscovered it (and named it) in August 1989.
Compare with <a href="lex_j.htm#jam">jam</a>. In terms of its minimum <a href="lex_p.htm#population">population</a> of 12 it
ties with <a href="#mazing">mazing</a> as the smallest p4 <a href="lex_o.htm#oscillator">oscillator</a>. But in terms
of its 6x6 <a href="lex_b.htm#boundingbox">bounding box</a> it wins outright. In fact, of all
oscillators that fit in a 6x7 box it is the only one with <a href="lex_p.htm#period">period</a>
greater than 2.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
...OO.
..O..O
O..O.O
....O.
O.OO..
.O....
</a></pre></td></tr></table></center>
<p><a name=monogram>:</a><b>monogram</b> (p4) Found by Dean Hickerson, August 1989.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
OO...OO
.O.O.O.
.OO.OO.
.O.O.O.
OO...OO
</a></pre></td></tr></table></center>
<p><a name=mooseantlers>:</a><b>moose antlers</b> (p1)
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
OO.....OO
O.......O
.OOO.OOO.
...O.O...
....O....
</a></pre></td></tr></table></center>
<p><a name=mosquito>:</a><b>mosquito</b> See <a href="#mosquito1">mosquito1</a>, <a href="#mosquito2">mosquito2</a>. <a href="#mosquito3">mosquito3</a>, <a href="#mosquito4">mosquito4</a> and
<a href="#mosquito5">mosquito5</a>.
<p><a name=mosquito1>:</a><b>mosquito1</b> A <a href="lex_b.htm#breeder">breeder</a> constructed by Nick Gotts in September 1998.
The original version had an initial population of 103, which was
then the smallest for any known pattern with superlinear growth
(beating the record previously held by <a href="lex_j.htm#jaws">Jaws</a>). This was reduced
to 97 by Stephen Silver the following month, but was then almost
immediately superseded by <a href="#mosquito2">mosquito2</a>.
<p>Mosquito1 consists of the classic <a href="lex_p.htm#puffertrain">puffer train</a> plus four
<a href="lex_l.htm#lwss">LWSS</a> and four <a href="#mwss">MWSS</a> (mostly in <a href="lex_p.htm#predecessor">predecessor</a> form, to keep the
population down). Once it gets going it produces a new block-laying
<a href="lex_s.htm#switchengine">switch engine</a> (plus a lot of junk) every 280 generations. It is
therefore an MMS breeder, albeit a messy one.
<p><a name=mosquito2>:</a><b>mosquito2</b> A <a href="lex_b.htm#breeder">breeder</a> constructed by Nick Gotts in October 1998.
Its initial population of 85 was for a couple of hours the smallest
for any known pattern with superlinear growth, but was then beaten by
<a href="#mosquito3">mosquito3</a>.
<p>Mosquito2 is very like <a href="#mosquito1">mosquito1</a>, but uses two fewer <a href="#mwss">MWSS</a> and
one more <a href="lex_l.htm#lwss">LWSS</a>.
<p><a name=mosquito3>:</a><b>mosquito3</b> A <a href="lex_b.htm#breeder">breeder</a> constructed by Nick Gotts in October 1998.
Its initial population of 75 was at the time the smallest for any
known pattern with superlinear growth, but was beaten a few days
later by <a href="#mosquito4">mosquito4</a>.
<p>Mosquito3 has one less <a href="lex_l.htm#lwss">LWSS</a> than <a href="#mosquito2">mosquito2</a>. It is somewhat
different from the earlier mosquitoes in that the <a href="lex_s.htm#switchengine">switch engines</a>
it makes are glider-producing rather than block-laying.
<p><a name=mosquito4>:</a><b>mosquito4</b> A slightly improved version of <a href="#mosquito3">mosquito3</a> which Stephen
Silver produced in October 1998 making use of another discovery of
Nick Gotts (September 1997): an 8-cell pattern that evolves into a
<a href="lex_l.htm#lwss">LWSS</a> plus some junk. Mosquito4 is a <a href="lex_b.htm#breeder">breeder</a> with an initial
population of 73, at the time the smallest for any known pattern
with superlinear growth, but superseded a few days later by
<a href="#mosquito5">mosquito5</a>.
<p><a name=mosquito5>:</a><b>mosquito5</b> A slightly improved version of <a href="#mosquito4">mosquito4</a> which Nick Gotts
produced in October 1998. The improvement is of a similar nature
to the improvement of mosquito4 over mosquito3. Mosquito5 is a
<a href="lex_b.htm#breeder">breeder</a> with an initial population of 71. At the time, this was
the smallest population for any known pattern with superlinear
growth, but it has since been superseded by <a href="lex_t.htm#teeth">teeth</a>, <a href="lex_c.htm#catacryst">catacryst</a> and
<a href="#metacatacryst">metacatacryst</a>.
<p><a name=mould>:</a><b>mould</b> = <a href="#mold">mold</a>
<p><a name=movingsawtooth>:</a><b>moving sawtooth</b> A <a href="lex_s.htm#sawtooth">sawtooth</a> such that no cell is ON for more than
a finite number generations. David Bell has constructed patterns
of this type, with a <i>c</i>/2 front end and a <i>c</i>/3 back end.
<p><a name=msmbreeder>:</a><b>MSM breeder</b> See <a href="lex_b.htm#breeder">breeder</a>.
<p><a name=multistatelife>:</a><b>multi-state Life</b> = <a href="lex_c.htm#colorizedlife">colorized Life</a>
<p><a name=multuminparvo>:</a><b>multum in parvo</b> (stabilizes at time 3933) A <a href="#methuselah">methuselah</a> found by
Charles Corderman, but not as long-lasting as his <a href="lex_a.htm#acorn">acorn</a>.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
...OOO
..O..O
.O....
O.....
</a></pre></td></tr></table></center>
<p><a name=mutteringmoat>:</a><b>muttering moat</b> Any <a href="lex_o.htm#oscillator">oscillator</a> whose <a href="lex_r.htm#rotor">rotor</a> consists of a closed
chain of cells each of which is adjacent to exactly two other rotor
cells. Compare <a href="lex_b.htm#babblingbrook">babbling brook</a>. Examples include the <a href="lex_b.htm#bipole">bipole</a>,
the <a href="lex_b.htm#blinker">blinker</a>, the <a href="lex_c.htm#clock">clock</a>, the <a href="lex_c.htm#cuphook">cuphook</a>, the <a href="lex_g.htm#graycounter">Gray counter</a>, the
<a href="lex_q.htm#quad">quad</a>, the <a href="lex_s.htm#scrubber">scrubber</a>, the <a href="lex_s.htm#skewedquad">skewed quad</a> and the p2 <a href="lex_s.htm#snakepit">snake pit</a>.
The following diagram shows a p2 example (by Dean Hickerson, May
1993) with a larger rotor. See <a href="lex_r.htm#ringoffire">ring of fire</a> for a very large one.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
OO.....
O.O.OO.
.....O.
.O..O..
..O....
..O.O.O
.....OO
</a></pre></td></tr></table></center>
<p><a name=mwemulator>:</a><b>MW emulator</b> (p4) Found by Robert Wainwright in June 1980. See also
<a href="lex_e.htm#emulator">emulator</a> and <a href="lex_f.htm#filter">filter</a>.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
.......O.......
..OO.O...O.OO..
..O.........O..
...OO.....OO...
OOO..OOOOO..OOO
O..O.......O..O
.OO.........OO.
</a></pre></td></tr></table></center>
<p><a name=mwss>:</a><b>MWSS</b> (<i>c</i>/2 orthogonally, p4) A middleweight spaceship, the third
most common <a href="lex_s.htm#spaceship">spaceship</a>. Found by Conway in 1970. See also <a href="lex_l.htm#lwss">LWSS</a>
and <a href="lex_h.htm#hwss">HWSS</a>.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
...O..
.O...O
O.....
O....O
OOOOO.
</a></pre></td></tr></table></center>
<p><a name=mwssemulator>:</a><b>MWSS emulator</b> = <a href="#mwemulator">MW emulator</a>
<p><a name=mwssoutoftheblue>:</a><b>MWSS out of the blue</b> The following reaction, found by Peter Rott
in November 1997, in which a <a href="lex_l.htm#lwss">LWSS</a> passing by a p46 <a href="lex_o.htm#oscillator">oscillator</a>
creates a <a href="#mwss">MWSS</a> travelling in the opposite direction. Together
with some reactions found by Dieter Leithner, and a LWSS-turning
reaction which Rott had found in November 1993 (but which was not
widely known until Paul Callahan rediscovered it in June 1994)
this can be used to prove that there exist <a href="lex_g.htm#gliderless">gliderless</a> guns for
LWSS, MWSS and <a href="lex_h.htm#hwss">HWSS</a> for every period that is a multiple of 46.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
O..O.................................
....O................................
O...O................................
.OOOO................................
.....................................
.....................................
.....................................
.....................................
.....................................
...................OO..............OO
..................OO...............OO
...................OOOOO.............
..OO................OOOO.............
..OO.....O...........................
........OOO.........OOOO.............
.......O.O.O.......OOOOO.............
........O..O......OO...............OO
........OOO........OO..............OO
.........O...........................
.....................................
.....................................
.....................................
.....................................
..O.......O..........................
.....................................
OOO.......OOO........................
.OO.OO.OO.OO.........................
..OOO...OOO..........................
...O.....O...........................
.....................................
.....................................
.....................................
.....................................
.....................................
.....................................
.....................................
.....................................
.....................................
.....................................
..OO.....OO..........................
..OO.....OO..........................
</a></pre></td></tr></table></center>
<p><a name=mwvolcano>:</a><b>MW volcano</b> (p5) Found by Dean Hickerson in April 1992.
<center><table cellspacing=0 cellpadding=0><tr><td><pre><a href="lexpatt:">
......O......
....O...O....
.............
...O.....O...
.OOO.OOO.OOO.
O...OO.OO...O
O.OOO.O.OOOO.
.O...........
...O.O.O.OO.O
..OO.OOO.O.OO
...O.O..O....
...O..OO.....
..OO.........
</a></pre></td></tr></table></center>
<p><a name=myexperiencewithbheptominosinoscillators>:</a><b>My Experience with B-heptominos in Oscillators</b> An article by
Dave Buckingham (October 1996) that describes his discovery of
<a href="lex_h.htm#herschelconduit">Herschel conduits</a>, including sufficient (indeed ample) <a href="lex_s.htm#stable">stable</a>
conduits to enable, for the first time, the construction of period <i>n</i>
oscillators - and true period <i>n</i> guns - for every sufficiently large
integer <i>n</i>. (See <a href="lex_h.htm#herschelloop">Herschel loop</a> and <a href="lex_e.htm#emu">emu</a>.)
<hr>
<center>
<font size=-1><b>
<a href="lex_1.htm">1-9</a> |
<a href="lex_a.htm">A</a> |
<a href="lex_b.htm">B</a> |
<a href="lex_c.htm">C</a> |
<a href="lex_d.htm">D</a> |
<a href="lex_e.htm">E</a> |
<a href="lex_f.htm">F</a> |
<a href="lex_g.htm">G</a> |
<a href="lex_h.htm">H</a> |
<a href="lex_i.htm">I</a> |
<a href="lex_j.htm">J</a> |
<a href="lex_k.htm">K</a> |
<a href="lex_l.htm">L</a> |
<a href="lex_m.htm">M</a> |
<a href="lex_n.htm">N</a> |
<a href="lex_o.htm">O</a> |
<a href="lex_p.htm">P</a> |
<a href="lex_q.htm">Q</a> |
<a href="lex_r.htm">R</a> |
<a href="lex_s.htm">S</a> |
<a href="lex_t.htm">T</a> |
<a href="lex_u.htm">U</a> |
<a href="lex_v.htm">V</a> |
<a href="lex_w.htm">W</a> |
<a href="lex_x.htm">X</a> |
<a href="lex_y.htm">Y</a> |
<A href="lex_z.htm">Z</A></b></font>

</center>
<hr>
</body>
